<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script>
    
        var inum01 = 123;
        var snum02 = "456";
        var bHah = true;

        alert(inum01 + snum02);//123456
        alert(inum01 + parseInt(snum02));//579


        // alert(bHah + snum02);


        alert(parseInt("10"));//10
        alert(parseInt("10.5"));//10
        alert(parseFloat("10.5"));//10.5
    
    
    </script>
</head>
<body>
    
</body>
</html>